Android: The Wi-Fi hotspot feature on Android phones lets you use your mobile data on multiple computers or tablets at once. The only problem is a lot of carriers have restrictions to prevent you from sharing your mobile data (which you're already paying for) for free. Computerworld posts a couple of workarounds.

First, you should know that, as with other kinds of tethering, your carrier may not be too happy with you going around their special Wi-Fi hotspot plans, and you can end up pissing them off and being charged extra (or in extreme cases, having your contract canceled). Also, these workarounds might not apply to every wireless carrier or device (it doesn't for me on T-Mobile with a Samsung Galaxy S2, but some commenters on Computerworld vouch for the method).

An alternative is to use a free app called FoxFi. It doesn't work with Android 4.1, though, and some carriers are blocking it from being downloaded, but you may be able to install it from an alternate location or with the QR code in the Play store.

If this trick works for you or you have any other suggestions, let us know in the comments below.